If you are referring to numbering captions in an appendix, as discussed in the article
How to number headings and figures in Appendixes in Microsoft Word | ShaunaKelly.com, note that caption labels are not stored with the document. Instead, they will be added to the Normal template. This means that you have to recreate the labels if you work on more than one computer. What you can do is store the labels as AutoText entries. See the article.